A preliminary investigation into last month’s Air India crash in Ahmedabad has revealed that both of the aircraft’s fuel control switches were in the cut-off position just moments before the fatal impact, effectively shutting down the engines.

The report, which contains cockpit voice recordings, describes misunderstanding between the two pilots in the closing seconds. One pilot is heard questioning another why the fuel switches were turned off. The second pilot denies doing so. According to aviation experts, it is highly unlikely that both switches were accidentally activated at the same time, creating more doubts about the sequence of events, BBC reported.

The crash resulted in the deaths of at least 260 passengers and crew. The only survivor, British national Vishwashkumar Ramesh, reportedly escaped the wreckage through a breach in the fuselage.

Air India has stated that it is fully cooperating with the ongoing investigation, while aircraft manufacturer Boeing expressed condolences to the families of the victims. The incident remains under active inquiry, according to BBC.